Tickets for the game - which will see the cost of playing double to £2 a line - go on sale on October 3, with players having the chance to win 1,000 guaranteed £20,000 prizes and the £10 million jackpot two Saturdays in a row.
The special draws will take place on October 5 and October 12.
The increase in the price of a ticket is the first since the lottery was introduced in 1994.
But Camelot said the payout for the average Saturday jackpot would increase from about £4.1 million to £5 million.
It also announced rises in the amount paid to those matching three numbers, from £10 to £25, and matching four numbers, from £60 to £100.
However some prize payouts are being reduced, with the reward for matching five numbers dropping by £500 to £1,000, and that for five numbers and the bonus number halving to £50,000.
Camelot UK managing director Andy Duncan said: "New Lotto will give players more ways to win more money and we have two fantastic events planned to celebrate the launch.
From October 3, players will receive a unique raffle number printed at the bottom of their ticket for every line of Lotto played giving them a chance of winning one of 50 guaranteed prizes of £20,000.